To solve this problem, we need to follow these steps:

1. Find the total number of mangoes in one tray:

   • Each tray has 5 rows with 6 mangoes per row.
   • So, the total number of mangoes in one tray is: $5 \times 6 = 30 \text{ mangoes}.$

2. Determine the cost per mango:

   • The total cost of the tray is $46.
   • Therefore, the cost per mango is: $\frac{46}{30} = 1.5333 \text{ dollars per mango}.$

3. Calculate the cost of 3 mangoes:

   • The cost for 3 mangoes is: $1.5333 \times 3 = 4.60 \text{ dollars}.$

Thus, the cost of three mangoes is $4.60. The correct answer is (D).

Would you like more details on any step?

Here are 5 related questions to expand your understanding:

1. How would the cost change if the price of a tray increased?
2. How many trays would be needed to purchase 90 mangoes?
3. What would the cost per mango be if the number of mangoes per row increased to 8?
4. How much would 12 mangoes cost at this rate?
5. What is the total number of mangoes you could buy with $100?

Tip: When working with unit rates, always break the problem down into smaller steps to find the per-item cost first.